A similar condition to that of corn may be met with in other positions on the sole. It is described by Rogerson as sand-crack of the sole[A], and is invariably met with around that portion of the sole in contact with the shoe.
[Footnote A: Veterinarian, vol. lxiii., p. 51.]
The animal is lame, and the shoe is removed in order to ascertain the cause. Nothing at first is noticeable except that the animal flinches when pressure is applied to the spot with the pincers, or the sole is tapped with the hammer.
On removing the sole with the knife, however, a distinct black mark is discovered, which, when followed up by careful paring, is often found to have pus at the bottom.
In this case the injury has resulted, as we have already intimated elsewhere, from causing the animal to wear for too long a time a shoe with too broad a web or insufficiently seated. Or it may have originated with the irritation set up by foreign and hard substances between the web of the shoe and the foot.
In his description of this condition Mr. Rogerson draws attention to the fact that the pus found should not be wrongly attributed to accidental pricking of the foot. He says:
'Considering that the cracks or splits are always found in the immediate vicinity of the nail-holes, a certain amount of discretionary skill is required in order that the lameness may be attributed to its proper cause. This is an instance in which the presence of the veterinary surgeon is imperative, in order to prevent undue blame being attached to the shoeing-smith. Misconception in these cases might very easily arise when parties concerned are disposed to accept an unskilled opinion, sometimes resulting in danger to the proprietor of the forge, not only of losing a shoeing contract, but also of being involved in other ways which would probably prove even more disastrous.
'Horses that stand on sawdust or moss litter are sometimes found with extensive discoloration of the horny sole in front of the frog. Their bedding material collects in the shoe as snow does, and forms a mass, which keeps a continued and uneven pressure upon the sole. A sound foot is not injuriously affected, but a very thin sole is, and so also is a sole which has been bruised by a picked up stone. Even a slight bruise becomes serious if pressure is allowed to remain active over the injured part. Lameness increases, serous fluid is effused between the horn and sensitive part, or even haemorrhage may take place.'[A]
[Footnote A: Hunting, Veterinary Record, vol. xiv., p. 593.]
The Treatment of Chronic Bruised Sole offers no special difficulty. Removal of the cause (in nearly every case incorrect bearing of the shoe) is the first consideration. That done, the lesion may be searched for and treated in the ordinary manner as described for corn. When pus is present it must, of course, be given exit, and an antiseptic solution applied to the wound. Should the sensitive structures be laid bare when allowing the pus to escape, then the wound so made should afterwards be protected with a leather sole and antiseptic stopping.